Big white circle for point light
The reason it's a big white dot is because the Point light size defaults to 10cm: 



The only way to get "rid" of the dot is to make the point light smaller (which makes the dot smaller), but then you'll have to crank up the Strength to compensate.  If you crank it up too much you'll probably get a ton of fireflies.  

The hard edges of the dot are because your glass has a roughness of 0.  If you set the roughness a little higher the edges of the dot will get softer. 

What I would actually recommend is to model a light bulb (or candle flame) for your lamp, and set it to have an Emission texture.  I think that'll give you the best results in the end.